The invention relates to a guide device in particular for the positioning of catheters in a body duct.
The problem is addressed in WO 02/34324 A2, in which guide wires connect a section made of a superelastic material with a section made of steel which is significantly stiffer than the first-mentioned section. The guide wire known from WO 00/40288 A1 has a shapable body on its distal section, the flexibility of which is changed continuously and should retain its shapable characteristics.
The problem that the guide wire tends to be moved during the withdrawal of the catheter is addressed in EP 0 714 315 B1. The guide wire revealed here is designed in such a way that its movement is clearly recognizable visually.
The guide wire described in DE 200 19 484 U1 exhibits basic non-ferromagnetic bodies at regular intervals. They are furnished with minimum quantities of ferromagnetic particles, whereby the guide wire consists of a hollow cylindrical tube made of a non-ferromagnetic material such as plastic, for example. It contains a cylindrical carrier which is marked with clusters of ferromagnetic particles at regular intervals. This guide wire is especially suitable for processes controlled through magnetic resonance tomography.
A filter fixture which catches embolic material in a blood vessel and also envelopes a guide wire is known from DE/EP 0 980 278 T1. Furthermore, a catheter is known from the last-named publication, which has an expandable stent, whereby the stent exhibits a first diameter and also a second expanded diameter and also has an expandable frame which can be expanded between a contracted and an opened condition. Furthermore, the catheter has a sleeve, whereby the sleeve is pulled back during its use in order to free the expandable frame cavity and the stent. The expandable frame can exhibit a lumen seal.
The catheter furthermore has a pump system which exhibits a first lumen designed to accept fluid under pressure and a second lumen designed to evacuate gas. The inflation seal has furthermore an inlet opening with a fluid connection to the first lumen of the pump system and an exit opening with a fluid connection to the second lumen of the pump system. The inflatable seal can exhibit a hose-shaped balloon.
A guide wire with a core wire is described in EP 0 826 389 B1. It has a number of thin wires twisted with each other. The core wire has a semi-circular cross-section and through it makes room for a channel for fluid passage. The guide wire and core wire are part of a catheter, the forward end of which is open and thereby enables fluid discharge in the lengthwise direction of the catheter.
A guide wire which exhibits an outer tube which is shaped from a flexible material without restoring force is known from EP 0 823 261 A2. Furthermore, the guide wire has an inner core wire which can be moved back and forth in the outer tube. The core wire has a distal end which, although it is flexible on the one side, exhibits a return force on the other side, but in certain manner such as that if possible the distal end protrudes bent in a prescribed manner especially at the distal end of the outer tube. For this purpose, the distal end of the outer tube is formed very flexibly.
A guide wire unit is described in EP 0 778 044 A2. A sensor unit in a hollow, flexible component such as a hollow tube can slide into it in order to stiffen the flexible components. The sensor unit has a flexible sensor sleeve and an inner sensor wire, whereby the distal end of the latter is bent in advance in a certain manner. The sensor unit serves, for example, to stiffen an electrode cable during the insertion of the cable through a vein to the heart of the patient.
A catheter which exhibits two balloons arranged behind each other at its forward end for the dilation of vessels is known from NL-A-9 500 283. The balloons can be subject to a medium which is under pressure through connections.
A guide device, called a guide wire is known, for example, from DE 100 17 147 A1. This guide wire consists of an outer wire thread which is shaped as a hollow thread as well as an inner thread which can be moved inside it. The wire thread has a curved guide tip at its distal end. It acts as a control element or pathfinder during the insertion of the guide wire.
The guide devices or guide wires mentioned are introduced into a body duct, for example, in a vessel such as a vein or artery so that a catheter can later be pushed along the guide wire. Different, narrow branches are to be entered with the guide wire, whereby the relatively stiff catheter is to be introduced afterwards. In the case of the last-mentioned guide wire, the curvature is prescribed at its distal end, so that the corresponding pre-shaped guide catheter with the correct curvature is to be selected. The diameter of such a guide catheter is relatively large as it is used as an outer guide. In the second step, the actual therapy catheter, for example, a balloon catheter, is to be pushed in later through the hollow of the guide catheter. The external guide catheter is relatively thick in the forward area because of its curvature. Furthermore, there is the danger that the forward part of the guide wire can slip out of the intended vessel at a branch of the vessel when inserting a relatively rigid therapy catheter without the use of a guide catheter.
Another guide device is known from U.S. Pat. No. 5,337,733. This guide device comprises a chamber lying between an inner wall and an outer wall, which can be sealed to the outside. The outer wall is formed by a flexible hose. The inner wall is also formed by a hose which, in contrast to the outer wall, can be deformed in the radial direction to the inside when a guide is introduced in the chamber. Furthermore, the outer wall can lie against the inner wall through the evacuation of the intermediate chamber in order to make the guide device stiff. The outer wall and the inner wall can attach to each other through attachment elements.
The invention is based on the task of creating a guide device of the kind mentioned at the beginning, which can be handled easily and is, above all, adequately flexible on one side, but also adequately stiff on other side.